Self monitoring static seal

Abstract

A seal for preventing leakage of fluid from between a first member and a second member the second member is capable of moving toward and away from the first member, the seal is adapted for engaged contact with the first member and the second member so as to prevent leakage of fluid between the first member and the seal and between the second member and the seal, the seal being more easily deteriorated than the second member such that friction between the seal and the second member wears the seal faster than the second member, the seal being adapted to retain a fluid tight seal against the second member as long as the seal has not worn beyond a specified depth; and a conductor for placement about the second member, the conductor being attached to the seal at the specified depth so as to contact the second member when the seal has worn to the specified depth, such that the existence of electrical discontinuity between the conductor and the second member indicates that the seal requires replacement, the conductor is positionally associated to the seal such that wear of the seal corresponds with movement of the conductor toward the second member; and the electrical continuity indicates whether the seal requires replacement.

That which is claimed is:  
     
       1. A seal for preventing passage of a fluid from between two members, said seal comprising: 
       sealing means for engaged contact with both members, so as to prevent passage of fluid between either of the members and the sealing means, said sealing means more readily deteriorated than one of the members, the sealing means being adapted to retain a fluid tight seal with the members as long as the sealing means has not deteriorated beyond a specified degree, and  
       a conductor for placement about said one member, said conductor being adapted to conduct electricity;  
       a dielectric polymer film electrically isolating the sealing means and the conductor from either of the two members, the two members and seal being stationary with regard to each other in fluid tight sealing contact; and  
       wherein the conductor is positionally associated to the sealing means, such that deterioration of the sealing means beyond said specified degree corresponds with electrical discontinuity of the conductor, such that the electrical discontinuity through the conductor indicates a requirement for seal replacement.  
     
     
       2. A seal according to  claim 1 , wherein said members are sliding or reciprocating with respect to each other. 
     
     
       3. A seal according to  claim 1 , wherein deterioration of the seal is by wear abrasion against a member. 
     
     
       4. A seal according to  claim 1 , wherein deterioration of the seal is by extended contact with the fluid. 
     
     
       5. A seal according to  claim 1 , wherein deterioration of the seal is by aging. 
     
     
       6. A seal according to  claim 1 , wherein deteriorated of the seal is by cracking. 
     
     
       7. A seal according to  claim 1 , wherein said conductor is comprised of two mating parts, one of which is associated with the seal and another of which is associated with one of the members, such that interconnection the two mating parts provides electrical continuity of the conductor and fluid tight engagement of the seal. 
     
     
       8. A seal according to  claim 1 , wherein said conductor comprises an electrically conductive polymer thick film applied in a liquid form to the sealing means. 
     
     
       9. A seal for preventing passage of a fluid between two members, said seal comprising: 
       sealing means for engaged contact with both members, so as to prevent passage of fluid between either of the members and the sealing means, said sealing means more readily deteriorated than one of the members, the sealing means being adapted to retain a fluid tight seal with the members as long as the sealing means has not deteriorated beyond a specified degree;  
       a conductor for placement about said one member, said conductor being adapted to conduct electricity; and  
       a dielectric polymer film electrically isolating the sealing means and the conductor from either of the two members;  
       wherein the conductor is positionally associated to the sealing means and to the dielectric polymer film, such that deterioration of the sealing means beyond said specified degree corresponds with electrical discontinuity of the conductor, such that the electrical discontinuity through the conductor indicates a requirement for seal replacement.  
     
     
       10. A seal according to  claim 9 , wherein the two members and the seal are stationary with regard to each other in fluid tight sealing contact. 
     
     
       11. A seal according to  claim 9 , wherein said conductor is comprised of two mating parts, one of which is associated with the seal and another of which is associated with one of the members, such that interconnection the two mating parts provides electrical continuity of the conductor and fluid tight engagement of the seal. 
     
     
       12. A seal according to  claim 9 , wherein said members are sliding or reciprocating with respect to each other. 
     
     
       13. A method of determining wear of a seal having a sealing means which prevents passage of a fluid between two members, said method comprising the steps of: 
       positioning the sealing means in engaged contact with both members, so as to prevent passage of fluid between either of the members and the sealing means, said sealing means chosen to be more readily deteriorated than one of the members, said sealing means designed and adapted to retain a fluid tight seal with the members as long as the sealing means has not deteriorated beyond a specified degree;  
       placing a conductor about said one member, said conductor being adapted to conduct electricity;  
       electrically isolating the sealing means and the conductor from either of the two members using a dielectric polymer film;  
       positionally associating the conductor to the sealing means, such that deterioration of the sealing means beyond said specified degree will correspond with electrical discontinuity of the conductor;  
       determining electrical continuity;  
       wherein determination of electrical discontinuity indicates a requirement for seal replacement.  
     
     
       14. A method of determining wear of a seal having a sealing means which prevents passage of a fluid between two members, said method comprising the steps of: 
       positioning the sealing means in engaged contact with both members, so as to prevent passage of fluid between either of the members and the sealing means, said sealing means chosen to be more readily deteriorated than one of the members, said sealing means designed and adapted to retain a fluid tight seal with the members as long as the sealing means has not deteriorated beyond a specified degree;  
       electrically isolating the sealing means and the conductor from either of the two members with a dielectric polymer film;  
       placing a conductor about said one member, said conductor being adapted to conduct electricity;  
       positionally associating the conductor to the sealing means, such that deterioration of the sealing means beyond said specified degree will correspond with electrical discontinuity of the conductor;  
       determining electrical continuity;  
       wherein determination of electrical discontinuity indicates a requirement for seal replacement.  
     
     
       15. A seal for preventing passage of a fluid from between two members, said seal comprising: 
       sealing means for engaged contact with both members, so as to prevent passage of fluid between said members and the sealing means, the sealing means being adapted to retain a fluid tight seal with the members as long as the sealing means has not deteriorated beyond a specified degree;  
       a conductor for placement about said one member, said conductor being adapted to conduct a signal; a dielectric polymer film electrically isolating the sealing means and the conductor from either of the two members,  
       a dielectric polymer film electrically isolating the sealing means and the conductor from either of the two members, and  
       wherein the conductor is positionally associated to the sealing means, such that deterioration of the sealing means beyond said specified degree corresponds with signal discontinuity of the conductor, such that the signal discontinuity through the conductor indicates a requirement for seal replacement.  
     
     
       16. The seal for preventing passage of a fluid from between two members defined in  claim 15 , wherein said signal comprises an electrical signal.